Abstract 162: Intralipid Protects the Heart in Late Pregnancy Against Ischemia/Reperfusion Injury as Effectively as Ischemic Conditioning
Introduction Recently, we found that hearts of late pregnant (LP) mice have higher vulnerability to ischemia/reperfusion (I/R) injury compared to hearts of non-pregnant mice. We have also shown that intralipid, a clinically safe compound, protects the hearts of male mice against I/R injury. Here we explored whether postischemic administration of intralipid can also protect the cardiac function of LP mice against I/R injury, and compared intralipid action with ischemic preconditioning (IPC) and ischemic postconditioning (IPOC).
Methods Isolated langendorff perfused LP mice hearts were subjected to 20 min ischemia followed by 40 min reperfusion. The hearts were assigned to four groups. 1) Control group (CTRL), hearts received KH solution throughout experiment; 2) Intralipid group (ITLD), hearts received 1% intralipid during reperfusion; 3) IPC group(IPC), hearts were subjected to 2 min of global ischemia and 5 min of reperfusion right before 20 min ischemia followed; 4)IPOC group, hearts were subjected to 6 cycles of 10s of reperfusion and 10s of ischemia during the initial 2 min of reperfusion. LVSP, LVEDP, LVDP and ±dp/dt were recorded throughout the experiments. At the end of the experiment, the infarct size (IS) was assessed by 1% triphenyltetrazolium chloride (TTC) staining.
Results Postischemic administration of intralipid significantly improved the cardiac function of LP mice. The rate pressure product (RPP) in LP mouse at the end of reperfusion was improved from 1617±287mmHg*beats/min in CTRL to 11556±784 mmHg*beats/min in ITLD group. The infarct size was also significantly reduced by intralipid to 17±2% from 57.4±5.2% in CTRL. Both IPC and IPOC significantly improved the cardiac function and reduced the infarct size (RPP=11123±2797mmHg*beats/min, IS=17.5±5.3 in IPC; RPP=11939±1762, IS=20.1±1.5 in IPOC, p<0.01 vs. CTRL). Interestingly, intralipid was as efficient as IPC and IPOC in protecting the hearts of LP mice against ischemia reperfusion injury as there were no significantly differences in cardiac function and infarct size between ITLD, IPC and IPOC group.
Conclusion. Intralipid protects late pregnant mice hearts against I/R injury as efficiently as ischemic conditioning.
- © 2012 by American Heart Association, Inc.